In recent years, wireless communication devices that perform wireless communication based on Bluetooth (Registered Trademark) which is a short-range wireless communication standard are becoming popular.
For example, Patent Literature 1 discloses a terminal interlinking system provided with a terminal device and a portable terminal device which are connected together via a short-range wireless communication. According to this system, a pairing that shares a shared key between the terminal device and the portable terminal device is performed. When re-establishing a connection to the terminal device having already undergone the pairing, the portable terminal device logs in the Operating System (OS) of the terminal device using the shared key, and establishes the connection to the terminal device.
For example, the short-range wireless communication and pairing by the terminal interlinking system disclosed in Patent Literature 1 that is a Patent Literature in Japan are performed among a smartphone, an electronic watch, and a wireless communication device which are now widely utilized. Note that the term “pairing” means a process of mutual authentication between wireless communication devices which establish a communication first time, and of registration of the information on the communication partner wireless communication device. In addition, when re-establishing a connection to the wireless communication having already undergone the pairing before, the wireless communication device establishes the communication while omitting the process like the mutual authentication.
In this case, some wireless communication devices that perform a short-range wireless communication are capable of establishing a pairing to only a single wireless communication device. An example is an electronic watch that is capable of establishing a pairing to only a single smartphone.
When such a wireless communication device is to be connected to another wireless communication device not having undergone the pairing before, a user is not able to give an operation for a pairing to another wireless communication device unless the user has given an operation for canceling the already established pairing.
In the case of, for example, the terminal interlinking system disclosed in Patent Literature 1, the operation for canceling the pairing is an operation for deleting the information on the shared key stored in the respective memories of the terminal device and the portable terminal device.
In addition, in the case of an electronic watch that is capable of establishing a pairing to only a single smartphone, when a start-over of pairing due to an error originating from the updating of the OS in the smartphone becomes necessary, the above deletion operation is necessary to cancel the already established pairing.
As explained above, according to the structures of conventional wireless communication devices that perform short-range wireless communication, in order to cancel the pairing, the operation for deleting the information on the shared key, and the like, from the memory of each wireless communication device is necessary. Hence, the operation still has a leeway for simplification. In addition, the operation for re-establishing the pairing once the pairing is canceled also has a leeway for simplification.
When, in particular, the shared key is shared as the pairing information like Patent Literature 1, and when the pairing information is deleted from the memory of only either wireless communication device, a future operation, such as whether to generate new pairing information to start over the pairing when re-establishing the connection or to delete the pairing information left in the memory of the other wireless communication device, is unclear. Such an unclear operation or control process may become an event that causes an error.